Co–P Bonds as Atomic-Level Charge Transfer Channel To Boost Photocatalytic H₂ Production of Co₂P/Black Phosphorus Nanosheets Photocatalyst

High photoinduced charge-carrier-separation efficiency plays a crucial factor in determining the photocatalytic activities of photocatalysts, and it remains challenging to steer the charge separation in an accurate manner. Herein, we address this important challenge by growing the Co2P cocatalyst onto the edges of black phosphorus (BP) nanosheets to craft Co–P bonds in the Co2P/BP nanosheets photocatalyst. As demonstrated by the photocurrent measurement and first-principle calculation, the Co–P bonds acting to faciliate atomic-level charge-flow steering can improve the photogenerated charge-carrier transfer between BP nanosheets and the Co2P cocatalyst, resulting in the improved photocatalytic performance of the Co2P/BP photocatalyst for H2 generation. As expected, the photocatalytic H2 generation rate of the Co2P/BP nanosheets photocatalyst is 39.7 times greater than that of bare BP nanosheets. Moreover, the Co2P grown on the edges of BP nanosheets inhibits the degradation of the BP nanosheets, resulting in its good stability for photocatalytic H2 production.